A primary focus of drug research is the development of analgesics to be used in pain management. New analgesics are often derived from herbs or plants. For example, capsaicin, a vanillyl alkaloid which is the pungent component of hot peppers, is an analgesic. (Cordell and Araujo (1993) The Annals of Pharmacotherapy 27:330; Levinson (1995) The Sciences January/February: 13-15)). Therapeutically capsaicin has been used successfully to treat several painful conditions including rheumatoid arthritis, osteoarthritis, and various peripheral neuropathic disorders. (Cordell and Araujo (1993)). However, the usefulness of capsaicin as a therapeutic is limited by its adverse effects including burning and erythema. Moreover, these side effects can persist over time.
Given the comprehensive therapeutic applications of analgesics, there is an enormous medical and health requirement for analgesics with limited side effects.